Proximal Gastrocnemius Musculotendinopathy in Dogs: A Retrospective Computed Tomography-Based Study

Objectives: The aim of this study was to describe the computed tomography features of proximal gastrocnemius musculotendinopathy in dogs, and to compare clinical presentation, associated lesions and outcomes with the existing literature. Methods: This retrospective study included 24 dogs diagnosed with proximal gastrocnemius musculotendinopathy based on contrast-enhanced computed tomography between January 2019 and April 2025. Signalment, clinical presentation, concurrent musculoskeletal or neurological disorders, imaging findings, treatment protocols and clinical outcomes were analysed. Results were compared to published magnetic resonance imaging- and radiograph-based series. Results: Dogs were predominantly active working breeds, with Border Collies representing 33% of cases. Chronic hindlimb lameness was the principal clinical sign. Computed tomography revealed soft tissue swelling and contrast enhancement at the origin of the lateral gastrocnemius head in all cases. Proximal gastrocnemius musculotendinopathy was isolated in 42% of cases, while others had concurrent cranial cruciate ligament rupture or lumbosacral stenosis. Conservative treatment, including analgesia and physiotherapy, led to favourable outcomes in 14 of 17 followed dogs. Clinical Significance: Proximal gastrocnemius musculotendinopathy is a cause of chronic lameness in athletic dogs. Computed tomography imaging, despite limitations compared to magnetic resonance imaging, provides useful diagnostic information. Early recognition of proximal gastrocnemius musculotendinopathy using computed tomography may prevent unnecessary surgical exploration of the stifle in dogs erroneously suspected of cranial cruciate ligament rupture.